Effect of silver nanoparticles on electrical and magnetic properties of reduced graphene oxide

Abstract

We report the effects of silver nanoparticles (Ag-NP) on morphological features of reduced graphene oxide (rGO) which show presence of atomic scale ripples and lattice defects. These entities present in the composite (Ag-rGO) modulates its magnetic and electrical properties. Graphene oxide (GO) and Ag-rGO are primarily paramagnetic while rGO is diamagnetic. Ag-rGO shows enhanced magnetization and hysteresis owing to the presence of defects. Magnetization is maximum in Ag-rGO synthesized using 1 mM of AgNO3. Further increase in AgNO3 concentration quenches magnetization due to excess C-O-C group present in Ag-rGO. Current-voltage (I-V) curves show transition from non-ohmic GO to ohmic rGO. In Ag-rGO, resistance decreases by at least four hundred times as compared to that of rGO and becomes n-type material. With increased Ag-NP concentration, rGO becomes susceptible to defects and loses its conductive nature. By optimizing Ag-NP concentration, both electrical and magnetic properties can be enhanced in Ag-rGO. © 2022 Elsevier Ltd